How to change the validity period of the undercloud certificates

Issue

• How to change the validity period of the undercloud certificates.
• Added some parameters to the /etc/certmonger/certmonger.conf like below but the certificates tracked by certmonger were not updated.

[root@director ~]# cat /etc/certmonger/certmonger.conf 
# This is the certmonger configuration file.  The format is a rather basic
# INI-style file.  See certmonger.conf(5) for notes about individual settings.
# · initial whitespace is ignored
# · whitespace between the key name and "=" is ignored
# · whitespace after "=" is ignored
# · trailing whitespace after values is ignored
# · comments begin with "#"
# · keys and section names are case-sensitive
# · there is no end-of-line continuation
#
# [defaults]
# notification_method = syslog
# notification_destination = daemon.notice
#
# [selfsign]
# validity_period = 1y
#
[local]
validity_period = 10y
#